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classification and characteristics

...pounds).
Utahraptor was considerably larger but is incompletely known.
Dromaeosaurus and
Velociraptor both reached a length of about 1.8 metres. There is debate as to whether
Microraptor, the smallest and most birdlike dinosaur known, is a dromaeosaur or a troodontid. Only about the size of a crow,
Microraptor appears to have possessed feathers. The single...

feathered dinosaurs

Microraptor, a genus discovered in the Liaoning deposits in 2000, possessed long feathers on both its arms and its legs, a condition suggested for
Archaeopteryx. Some paleontologists contend that such a four-winged configuration implies that flight evolved through a four-winged gliding stage. The phylogenetic position of
Microraptor, however, suggests that it diverged from...